Mat, not sure if this interest you at all, but this just popped into my head when reading your Dad’s likes.
How about something like a Saxophone playing, and out of the Sax it’s blowing bubbles. Each bubble coming out of the Sax is getting larger & larger. Inside each bubble is something different. You could have music notes in 1 or 2 of them, then white anemones in 1 or 2, maybe a few small animals in 1 or 2 and the largest top bubble would have a heart in it, maybe with your Dad’s name on a ribbon around it. Of course, for the details I see (in my head) it would have to be a good size piece. It would make a cool back piece. I see the top bubble about 3” in diameter. If you didn’t like the Saxophone idea, it could be a radio and these things are coming out of the speakers. I think you get the idea.

I lost my Dad 3 years ago and now have 2 memorial pieces. The 1st one for me was very easy. We both were in the military and I’m the youngest & only one in my family that followed Dad‘s footsteps. So my 1st one is on my right ribcage. It’s my skin torn open, my heart showing and Dad’s dog tags hanging around it. My 2nd one was easy too. It’s my Dad’s portrait on my left ribcage of him in 1952 @ 20 years old. I feel your pain and yes, the tattoo’s do help in the healing process. Both of my memorial pieces were done on the same calendar day I lost my Dad (1 year apart) and I was on the table getting inked during the time-of-day Dad took him last breath. Something Personally I want to do.
Good luck with your design & healing.
Dave…